Method of solubilizing vitamins a, b2, d2 and e



United States Patent 2,875,195 METHOD or SOLUBILIZING VITAMINS 2, D, AND E a isocyanato esters of the structure OCN(CI -I ),,C( )OR" Wilbert J. Humphlett and Charles V. Wilson, Rochester, 9r 2 5 g g g 'a g g g g gg N. Y., assignors to Eastman Kodak Company, Roch- IS a W 0 e m eger om o n I s g ester, YWa corporation of New Jersey from 1 to 6, for example, may also be employed. Isocyanato esters such as those derived from p-ammophenylace- No Drawing. Application August 9, 1956 10 tic or p-aminophenylsuccinic acids also fall within the ,seTi3lN11'603J93 scope of our invention. a V The following examples are intended to ilustrate our invention but are not intended to limit it in any way: This invention relates to new compositions of matter 15 Example L-Reaction of Wtalmm A with d'methyl obtained from water-insoluble vitamins and more par- .socyanatog Mamie ticularly to water-soluble vitamins, and their method of Vitamin A reacted with dimethyl a-isocyanatoglutarate production. T t to form 2-[3,7-dimethyl-9-(2,6,6-trimethyl-l-cyclohexen- Vitamins have assumed an ever-increasing importance l-yl) -2,4,6,8-nonatetraenylcarbamato] 1 glutaric acid (soin medical treatment and their value to the human sys- 0 dium salt) according to the following 95 o p cm d on. o t o cn=enc =orron =ond=oncmon Comm @5 3 i i i I+H-O-N,=,C=O (CHflrCChCH:

CH? on. r on, v CQzNa it on=ono=onon=onc=onomoooNnoH ,(CHrhC QaN G tem is well known. However, it has long been desired to A solution was prepared of 3.33 g. (0.012 mole) of find some way of making these materials water-soluble 35 crystalline vitamin A alcohol (M. F. 63-64") E (1%, so they would be more easily absorbed by the human body. 1 our.) (325 In/L) =l820,. 2.09 g. (0.01 1 mole) of di- Various ways are known in the prior art of solubilizing methyl a-isocyanatoglutarate '(B. .P. 8 3 at 0.5 mm, complex molecules, but, for the most part, these have n 1.4446), 1.8 ml. of anhydrous pyridine and 23 ml. been unsuitable since it has also been necessary that of anhydrous benzene in a.50,rnl. amber flask. 'Ifhe these materials, once .they were made water-soluble, 9 solution was refluxed for 1 hour min. protected from would be non-toxic and the solubilizing groups would atmosphericmoisture by-a calcium chloride tube. After be acceptable tothe human system. t removal of the solvent in vacuo, the' corresponding We have found a method of solubilizing vitamins urethane-ester was obtained as a viscousoil, E (1%, which are normally waterinsoluble. When taken inter 1 cm.) (325 m )=990 and having a characteristic nally the normal hydrolytic cleavage of these solubilized carotenoid spectrum in the infrared, To a solution of the vitamins results in amino acids which. are acceptable to ester in 95% ethyl alcohol was added 0.9 g. of sodium the human system and are themselves beneficial. o I hydroxide pellets dissolved in 20 ml. of alcohol and the One object of this invention is to provide water-solu reaction mixture swirled at room temperature for 30 ble vitamins. Another object is to provide amethod of min. The resulting sodium salt was collecteduand washed solubilizing vitamins so that they may be taken orally. with ethyl alcohol and then ethylether yielding 4.17 g. A further object is toprovide a non-toxic water-soluble (83% of theory) of a yellow, free-flowing powder, E vitamin. g j v (1%, 1 cm.).(325 m t)=885, M. P. 360 and having a r The above objects are obtained by reacting water-insolcharacteristic carotenoid infrared spectrum. uble vitamins with an isocyanato ester and then hydroly- The solubility of this product was demonstrated byzing with a suitable basic material. Our preferred em dissolving 2.0 g. of thesodium salt, in 5.0 ml. of water bodiment is to use an isocyanato ester derived from giving a yellow, homogeneous and clear solution. glutamic or aspartic acid, but adequate solubility is fre- A solutionof the salt yielded the correspondingacid quently attained with the .isocyanato esters from the upon addition of dilute hydrochloric acid, E (1%., 1 cm.) simpler amino acids such as glycine, a-alanine, leucine, (325 m =765, M. P. 80". and the like. Analysis.--Calcd for C H O N: C, 67.9; H, 8.1;N, Suitable basic materials include the hydroxides and 1, 3.0. Found: C, 67.7; H, 8.3; N, U 1: car o of Sodium, Potassium and 1ithium,alkyl pri: All analyses in the ultraviolet spectrum employ solumary, secondary and tertiaty amines, and the like. tions prepared in ethyl alcoho N The following general equation illustrates the type of y reactions involved: Example 2.Reaction of vitamin A with dime tf iy l a-i'so- ROH+OCNCHR'COOR"- ROCONHCHRCOOR"- cymosmmae ROCONHCHR F o 'By a method identical to that described above, employ- R represents the vitamin radical or the vitaminmole ment of dimethyl a-i'socyanatosuccinate (B. P. 65 at 0.5 cule less the hydroxyl group. R may be H, alkyl such mm., r1 ?,1.4455) in a reaction with crystalline vitamin as CH C H and (CH CH, (CH in which n is a whole integer from 1-6 or aryl such as C 11 2 CH COOR", and CH CH COOR". C H or some other lower alkyl.

Although the equation shown indicates that the isocyanate is derived from the'esters of a-amino acids,

A also yielded a water-soluble product, E (1%, 1 cm.)

Patented Feb. 1

Example 3.Redction of vitamin D (calciferol) with dimethyl oi-isacyanatoglutarate Vitamin D (calciferol) reacted with dimethyl a-isocyanatoglutarate and saponified as follows:

CO2Na HO-NHC O O A solution of 5.0 g. (0.013 mole) of vitamin D (M. P. 114, E (1%, 1 cm.) (263 I I )=467), 2.3 g. (0.011 mole) of dimethyl a-isocyanatoglutarate, 5 ml. of pyridine and 30 ml. of benzene was refluxed for 2 hours and the solvent removed under reduced pressure. The urethaneester, obtained as a viscous oil, was dissolved in a solution of 1.58 g. of potassium hydIQXide in 95% ethyl alcohol and refluxed for 45' min. The potassium salt, precipitated from the cooled solution, was collected and rinsed with acetone and then with ethyl ether yielding 6.2 g. (84%) of a white, free-flowing powder, M. P. 240, E (1%, 1 cm.) (265 mu) =208 in water solution. This product is readily soluble in water.

A water solution of the potassium salt was acidified with hydrochloric acid giving the corresponding acid, M. P. 83", E (1%, 1 cm.) (263 mn)=289.

Analysis.--Calcd for C H O N: N, 2.5. Found: N, 2.4. r

The sodium salt was prepared by dissolving the correspondingacid in an ethyl alcohol solution containing a slight excess of sodium hydroxide. This product, M. P. 318", is soluble in water.

The ammonium salt was prepared by dissolving the corrQSPQnding acid in ethyl alcohol and adding an excess of concentrated ammonium hydroxide solution. Evaporation under reduced pressure left the solid ammonium derivative, M. P. 180

1 E"(1%,1cm.) (2.68 m t,)=210 in water solution. This product is readily soluble in water.

Example 4.-R'eaction of vitamin E with dimethyl a-isocyanatoglutarate Vitamin E, reacted with dimethyl a-isocyanatoglutarat to form a-tocopheryl-2-carbamatoglutaric acid (sodium salt) according to the following; equation:

cm em onon.

on C OgNA -M 000 c amounts,

' charcoal and filtered. To this A solution of 40.6 g. (0.09 mole) of a-tocopherol (93.7% a-tocopherol, 95.5% total tocopherols), 16.1 g. (0.08 mole) of dimethyl a-isocyanatoglutarate and 200 ml. of anhydrous xylene was refluxed for 48 hours. After removal of the solvent under reduced pressure, the residual ester was obtained as an orange oil. The ester was saponified by warming with a solution of 7 g, of sodium hydroxide in 200 ml. of alcohol for 45 min. The solid product was collected and washed with acetone yielding 35.8 g. (69.5%) of a. tan powder.

For further purification the salt was dissolved in ml. of water and the solution extracted with ether. The aqueous phase was separated, warmed with powdered solution was added an excess of dilute hydrochloric acid and the precipitated solid acid product was collected and dried. The acid was dissolved in alcohol and the solution warmed with charcoal and filtered. To this solution was added a 5% excess of sodium hydroxide dissolved, in alcohol. The precipitated product amounted" to 22.1, g. (62%, ref eovery), E (1%, 1 cm.) (283 m )=24.2, M. P. 292.".

To demonstrate the solubility of this product, 1 g. of the salt was dissolved readily in 2 m1. of water.

A solution of the salt gave the corresponding acid upon acidification with hydrochloric acid, E (1%, 1 cm.) (283 m .)=35.6, M. P. 107.

Analysis..--Calc d for C35H51O7NI C, 69.7; H, 9.4; N, 2.3. Found: C, 70.2; H, 9.2; N, 2.3.

Analyses in the infrared, of both the salt and the acid gave curves having characteristics of the vitamin E molecule.

Example 5.Reaction of vitamin E with dimethyl u-iso- *cyanatosuccinate By a method identical to that in the foregoing example, 48.8 g. (0.11 mole) of a-tocopherol and 18.7 g. (0.10 mole) of dimethyl u-isocyanatosuccinate were reacted and subsequently saponified with 8.3 g. of sodium hydroxide yielding 41.3 g. (66%) of a water-soluble product, M. P. 234.

The corresponding acid was prepared from the salt, E (1%, 1 cm.) (283 mu.)- -32.7.

Analysis.-Calcd for C H Q- N: C, 69.3; H, 9.4; N, 2.4, Found; C, 69.4; H, 9.4; N, 2.4.

Vitamins for the most part are characterized by certain steroidal and isoprenoidal configurations and are of par, ticular value in dietary programs and are of value in medicine and nutrition. These waterasoluble compounds are particularly adaptable to injection or oral administration. Due to their solubility, these derivatives promise to constitute therapeutic preparations more readily absorbed in metabolic processes than the parent substances which are not water soluble. They are also characterized by the fact that normal hydrolytic cleavage of the molecule will produce an amino acid which would have no detrimental efiect upon the hu an system.

Our invention relates to vitamins which are insoluble 0 0r sparingly soluble in water and includes, vitamins A,

B (riboflavin), D (calciferol), E, and the like.

then NaO H8 CHI CH: CH:

cigcmithawmnemcmnbaea.

t We claim: 1 I. A composition of matter having the formula R p f n'ooomrbn (orn).ooon" it come I H NHGO H:):C0:Na 41. A solubilized vitamin E having the following formu a:

CH3 CH3 CH; CH:

OH COONa.

H NHCOO H910 OlNa 3 5. A solubilized vitamin B as follows:

COzNB CHaOCONH H E): HmOOINa 6. A solubilized vitamin E as follows:

CH CH; CH; CH: O a I CH (CH2)aCH(CHa)zCH(CHz)3CHCHz COOK H NH0 00-- HaCOOK 7. A process of solubilizing vitamin A comprising reacting it with an isocyanato ester having the following general formula:

in which R is an alkyl group having 14 carbon atoms, n is a whole integer of 1 to 6 and R is selected from the class consisting of hydrogen, alkyl having 1-3 carbon Na, K,;an d Ligand vitamin Ahaving the following for- I I is the following formula:

6 atoms andCOORand hydrolyzing the COOR group to form an alkali metal salt.

8. A process of solubilizing comprising reacting it with an isocyanato ester having t OtlN-OH (H2)C00R in which R is an alkyl group havingl-4 carbon atoms, 11 is a whole integer of 1 to6 and R is selected from the class'consis'ting of hydrogen, alkyl-having l-3 carbon atoms and COOR and hydrolyzing the COOR group toform an alkali metal salt.

9. A process of solubilizing vitamin D (calciferol) comprising reacting it with an isocyanato ester having the following formula:

(CHzh-COOR in which R is an alkyl group having 1-4 carbon atoms, n is a whole integer of 1 to 6 and R is selected from the class consisting of hydrogen, alkyl having 1-3 carbon atoms and COOR and hydrolyzing the COOR group to form an alkali metal salt.

10. A process of solubilizing vitamin E comprising reacting it with an isocyanato ester having the following formula:

CON-4:318:

cum-coon in which R is an alkyl group having l-4 carbon atoms, n is a whole integer the class consisting of hydrogen, alkyl having 1-3 carbon atoms and COOR and hydrolyzing the COOR group to form an alkali metal salt.

11. A process of solubilizing vitamins selected from the class consisting of vitamins A, B D and E by reacting the vitamins with an isocyanato ester having the following general formula:

DON-45H ((iHsh-COOR in which R is an alkyl group having l-4 carbon atoms, n is a whole integer of 1 to 6 and R" is selected from the class consisting of hydrogen, alkyl having 1-3 carbon atoms and COOR hydrolyzing the COOR group to form an alkali metal salt.

12. A process of making an urethane of vitamin A comprising reacting it with an isocyanato ester having the following general formula RI OCN-H HZ)n 'COOR in which R is an alkyl group having l-4 carbon atoms, n is a whole integer of l to 6 and R is selected from the class consisting of hydrogen, alkyl having: 1-3 carbon atoms, and COOR.

13. A process of making an urethane of vitamin B (riboflavin) comprising reacting it with an isocyanato ester having the following general formula I?! DON-(3H (CHzh-COOR in which R is an alkyl group having 1-4 carbon atoms, n is a whole integer of 1 to 6 and R is selected from the class consisting of hydrogen, alkyl having l-3 carbon atoms, and COOR.

14. A process of making an urethane of vitamin D vitamin B (riboflavin) of 1 to 6 and R is selected from acme, 119-5;

in which R is an alkyl group having 1-4 carbon atoms, n is a whole integer of 1 to 6 and R' is selected from the class consisting of hydrogen, alkyl having 1-3 carbon atoms; andCOOR;

15. A process of making an. urethane of vitamimE;

comprisingreacting it with an isocyanato ester having the following a generalformula RI OCN-(IJH (chm-000R in which R is an alkyl group having 1-4 carbon atoms, n is a whole integer of 1 to,6 and R is selected from the 85 class consisting of hydrogen, alkyl having 1:31081'11011 atoms, and,C.0OR v a 16. A process of making an urethane of vitamins selected from the class consisting of vitamins A, 3;, D

* and E by reacting the vitamins withan isocyanato ester having the following: general: formula:

R OONALH (anon-coon in which R' is an alkyl group; having 1'-4 carbon atoms;

n is a whole integer of 1 to Gand R" is selected' 'from'tl'ie class consisting of hydrogen, alkyl having I-S-carbon atoms, and COOR.

References Cited in the file of thisapatent UNITED STATES PATENTS 2,188,878 Lautenschlager et a1 Jam. 30} 1940 

1. A COMPOSITION OF MATTER HAVING THE FORMULA
 5. A SOLUBILIZED VITAMIN B2 AS FOLLOWS: 